A visual assessment of the returned set screw identified an implant fracture as reported.The top portion of the set screw was sheared off at approximately half the depth of the torx detail.A functionality assessment could not be performed due to the damaged condition of the set screw.A dhr review was performed for the complaint lot and there were no manufacturing anomalies identified.The device met all required specifications prior to being released to distributable inventory.This lot has been available for distribution since 12/19/19.There have not been any other reported complaints with this lot.Experienced hardware staff were consulted for input regarding the implant set screw malfunction.None of the company staff had previously seen a set screw malfunction in this manner.The set screw is used to secure the cross bar implant to the locking plate, which is distributed with the set screw contained within the threaded hole of the implant when distributed.When rotational force is applied to the set screw, it is almost completely captured within the threaded hole of the implant.It is unclear how a system set screw could be fractured when being tightened.It could be possible that a set screw may fracture if excessive rotational force was applied or if it was rotated while cross-threaded in the implant.Excessive rotational force may fracture the set screw.A torque-limiting handle is provided to limit the amount of rotational force applied to the set screw.A cross-threaded set screw would not rotate as intended and may concentrate applied force and result in a malfunction.It is unclear how a set screw could be cross-threaded.The implant is provided as an assembly, which includes the set screw contained within the threaded hole of the implant.
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